You're trying a "very good" Zuiko and comparing it to the "superb" Zeiss Planar. You have been spoiled with the Zeiss lens.
I had an Olympus OM-20 and used the Zuiko 1,8/50 lens and was happy with it as my main small format camera until I bought an old Kodak Retina Ib with the Schneider Xenar 2,8/50. The Zuiko was sharp, but the Xenar is razor sharp.
I agree. I have a Retina IIIc.
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